The present invention relates to an automatic fuel supply stopping device to be incorporated in a combustion equipment such as a gas heater into which fluid fuel is steadily supplied to be ignited and maintained burning.
The combustion equipments using town gas have usually often employed, as gas leakage preventing devices, so-called automatic safety devices, the thermo-responsive devices as of bimetal. Such thermo-responsive device of prior art comprises a fluid intercepting mechanism interposed in a channel for gas supply to a combustor and this thermoresponsive device is normally heated by a part of combustion heat produced from the combustor. During combustion, the device is actuated to hold said fluid intercepting mechanism in the passage opening state (i.e., the state in which a gas stream steadily flows through the gas pipe and maintains the combustion). Upon disappearance of gas flame due some causes, said thermo-responsive device is cooled and the fluid intercepting mechanism is automatically changed over to the passage blocking state (the state in which the gas stream flowing through the gas pipe is blocked) and held in such state. In such termo-responsive device of prior art utilizing bimetal or like, the fluid intercepting mechanism can not be perfectly driven to its passage blocking state unless said thermo-responsive device is sufficiently cooled and, in consequence, a plenty of gas still supplied often leaks into the exterior during a period from extinction of the gas flame to actuation of the fluid intercepting mechanism. This has often caused gas-poisoning and gas-explosion.